JP2002315739A - Hemoglobin concentration measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hemoglobin concentration measuring apparatus by which by using orange color or reddish orange color as the third wave length except conventional near infrared and red color, change in transmitted light caused by change in met- hemoglobin MetHb is detected under a condition with a good S/N ratio and discrimination between met-hemoglobin MetHb and reduced hemoglobin RHb is made easy and an appropriate measurement of the met-hemoglobin MetHb can be performed. SOLUTION: A light receiving means 6 in which a light source 3 emitting a light wave length in a reddish orange color region as the third wave length is used as a new light source and a light emitted from each light source and passing through or reflected from a living body tissue is received, an extinction degree ratio operating means 15 in which based on fluctuation of a received light outputting signal in each wave length from the light receiving means caused by pulsation of the blood, extinction degree ratios Φ among wave lengths are operated and a concentration ratio operating means 16 by which based on output from the extinction degree ratio operating means, at least, concentration ratio between the reduced hemoglobin and the met-hemoglobin is operated are provided and the appropriate measurement of the met-hemoglobin MetHb can be performed and concentration displaying and alarm displaying of it can be respectively performed by a clinically effective and convenient system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to measurement of oxygen saturation of arterial blood and measurement of hemoglobin concentration using a pulse oximeter or the like, and more particularly to measurement of methemoglobin concentration.

[0002]

2. Description of the Related Art In a conventional pulse oximeter, when near-infrared light and red light are incident on a living tissue, the ratio of the pulsation fluctuation of the light attenuation degree of the incident light in the living tissue is calculated. It is configured so that arterial blood oxygen saturation can be measured non-invasively from the results.

[0003] However, the measurement principle of the pulse oximeter is described in Japanese Patent Publication No. 53-264 proposed by the present applicant.
As shown in Japanese Patent Publication No. 37, it is conventionally known. Therefore, the measurement principle of the pulse oximeter will be briefly described as follows.

[0004] For example, a living tissue R is schematically divided into a blood layer R1 and a layer R2 of a tissue excluding blood (hereinafter, referred to as a pure tissue). It is assumed that the thickness of the layer R2 is constant. Therefore, when the living tissue R is irradiated with light, the incident light amount I0 is reduced by the living tissue R, and the transmitted light amount passing through the living tissue R becomes I.
When the thickness of the blood layer R1 increases by .DELTA.Db due to the pulsation, the amount of transmitted light decreases to (I-.DELTA.I). In this case, the dimming degree ΔA at the change ΔDb in the thickness of the blood layer R1 is obtained by the following equation.

ΔA = log [I / (I−ΔI)]

When light of two different wavelengths λ1 and λ2 is incident on the living tissue R, the ratio Φ of the extinction degrees ΔA1 and ΔA2 of the pulsation at each of the wavelengths λ1 and λ2 is approximately expressed by the following equation. What is shown has been confirmed by logic and experiment.

[0007]

(Equation 1)

Where Ei is the extinction coefficient of hemoglobin,
Fi is the scattering coefficient in blood, i = 1,2 is the light wavelength λ1
, Λ2. Further, assuming that the light absorbing substances in blood are only oxyhemoglobin and reduced hemoglobin, the absorption coefficient Ei of hemoglobin is expressed by the following equation.

[0009]

(Equation 2)

Here, S is the oxygen saturation, and Eoi and Eri are the extinction coefficients of oxyhemoglobin and reduced hemoglobin, respectively. Here, when the above equation (2) is substituted into the above equation (1),
The following equation is obtained.

[0011]

(Equation 3)

In the above equation (3), Eo1, Er1, Eo2,
Since Er2, F1, and F2 are known values, Φ =
By measuring ΔA1 / ΔA2, substituting it into the above equation (3), and solving for S, the oxygen saturation S can be obtained.

[0013]

In the above-mentioned conventional pulse oximeter using two wavelengths of near-infrared light and red light, if methemoglobin MetHb is present in blood, the display of oxygen saturation is reduced. However, since the methemoglobin MetHb concentration cannot be measured, the presence and concentration of methemoglobin MetHb in blood was unknown until blood was collected and measured with a carbon monoxide oximeter (CO-Oximeter) or the like.

However, when arterial blood pulsates, it is theoretically possible to measure the concentration ratio of n light absorbing substances in blood by using n light wavelengths. Therefore, oxygenated hemoglobin O2 Hb and reduced hemoglobin RH
It is theoretically impossible to measure the concentration of three types of hemoglobin, b and methemoglobin MetHb, at two wavelengths, and at least three light wavelengths are required.

However, in practice, the influence of tissues other than blood causes measurement errors. Therefore, in order to accurately measure the concentrations of n light absorbing substances in blood, a method using n + 1 light wavelengths is preferable. The present applicant has developed a blood component concentration measuring apparatus using these methods, and has filed a patent application (see Japanese Patent Publication No. 5-88609). In addition, since other light absorbing substances such as carboxyhemoglobin (COHb) and bilirubin also exist in blood, if these effects are to be eliminated, the number of light wavelengths used further increases and the equipment cost also increases. There are difficulties to do.

Considering the addition of a third wavelength for measuring methemoglobin MetHb to a conventional pulse oximeter (see Japanese Patent Application Laid-Open No. 5-228129), the wavelength longer than the red color is shown in FIG. As shown in
Oxygenated hemoglobin O2 Hb and methemoglobin MetHb
Since the ratio of the extinction coefficient of the methemoglobin MetH is substantially constant even if the third wavelength is provided in this wavelength band,
b It is difficult to detect intrinsic changes with high sensitivity.

On the other hand, Scharf proposes to use a green wavelength band (see US Pat. No. 5,830,137), but the light absorption of all hemoglobins is as shown in FIG. The light absorption of oxyhemoglobin O2Hb in the wavelength band of 500 to 620 nm is more than 10 times that in the wavelength band of 660 nm. Therefore, the light transmitted through the blood becomes weak, and it is difficult to measure the S / N ratio in the above-mentioned band with a good S / N ratio.

Therefore, the present inventors use the third wavelength of orange or red-orange in addition to the conventional near-infrared light and red light to reduce the change in transmitted light due to the change in methemoglobin MetHb. It has been found that detection can be performed with a good S / N ratio, and that it is possible to easily discriminate between methemoglobin MetHb and reduced hemoglobin RHb, thereby enabling appropriate measurement of methemoglobin MetHb.

That is, when the third wavelength is, for example, 805 nm in the near infrared and 621 nm in orange, the concentration ratio between various reduced hemoglobin RHb and methemoglobin MetHb is Φ12 and Φ13, respectively. The values were discussed. As a result, 80
In the case of near-infrared light of 5 nm, reduced hemoglobin R
In both changes of Hb and methemoglobin MetHb, the directions in which Φ12 and Φ13 change are almost the same, and it has been found that it is difficult to discriminate between reduced hemoglobin RHb and methemoglobin MetHb (FIG. 10).
reference). On the other hand, in the case of the orange color of 621 nm, it was found that the change in reduced hemoglobin RHb increases the orthogonality between the direction in which Φ moves and the direction in which methemoglobin MetHb moves (FIG. 9). reference).

The light absorption of methylene blue used for treatment of methemoglobinemia has a peak at 668 nm, and the third wavelength of 621 nm is far from the peak of methylene blue. It was confirmed that the measurement could be performed with less error even during treatment.

Therefore, the main object of the present invention is to use the orange or red-orange color as the third wavelength in addition to the conventional near-infrared light and red light to reduce the change in transmitted light due to the change in methemoglobin MetHb. In addition to detecting the methemoglobin MetHb from the reduced hemoglobin RHb while detecting the methemoglobin MetHb with a good S / N ratio, the methemoglobin MetH
It is an object of the present invention to provide a hemoglobin concentration measuring device capable of appropriately measuring b.

Further, conventionally, methemoglobin M in blood
methemoglobin MetHb produced by the concentration of etHb
It is known that bloodemia occurs due to the following causes.

(1) Congenital reductase deficiency (2) Inhalation therapy of nitric oxide (3) Administration of vasodilator such as nitrite (4) Administration of local anesthetic such as prilocaine (5) Aniline pesticide Poisoning by

Among the above-mentioned causes of methemoglobin MetHbemia, (1) is found in neonates, and the concentration of methemoglobin MetHb in blood is 10%.
%, The skin becomes darker, the blood becomes brown, and no improvement is seen by oxygen inhalation. That is, at the bedside, when blood collected is dropped on filter paper and brown without discoloring red, methemoglobin M
Diagnosis of etHb isemia. In addition, since blood collection is a heavy burden on newborns with low blood volume, the ability to non-invasively determine whether methemoglobin MetHb is present in the blood can provide significant benefits.

The above (2), (3) and (4) show that methemoglobin MetHb is added to the blood due to the treatment of the patient.
The physician performing the treatment is aware of the possibility that methemoglobin MetHb may be generated in the blood, so blood is sometimes collected and the concentration of methemoglobin MetHb is measured using a carbon monoxide oximeter or the like. By measuring or suppressing the dose of the drug, an increase in the blood concentration of methemoglobin MetHb is prevented. In such a situation, a monitor that continuously measures the concentration of methemoglobin MetHb in blood and generates an alarm when the concentration exceeds a certain level is extremely useful.

Furthermore, in the above (5), when such a patient is found unconsciously, there are cases where it is known that he or she has taken pesticides, and cases where it is not even known that he is addicted to drugs. Therefore, if it is known that methemoglobin MetHb is present in the blood at the time of being accommodated in an ambulance, it is possible to perform an early treatment action, which can contribute to not only improving the prognosis of the patient but also reducing medical expenses. .

As described above, conventionally, there is no method for continuously measuring the methemoglobin MetHb concentration in blood, and methemoglobin in blood is not collected until abnormalities such as cyanosis occur in a patient and blood is collected. In the background that the presence of MetHb is often unknown, for example, even if the exact blood methemoglobin MetHb concentration is not known, the indication of “presence” / “absence” at the boundary of 5%, It is also clinically effective to display three levels of methemoglobin MetHb such as "absent" / "possible" / "dangerous".

Therefore, another object of the present invention is to provide a hemoglobin concentration display method capable of displaying the methemoglobin MetHb concentration measured by the hemoglobin concentration measuring device in a clinically effective and simple manner. It is to provide a measuring device.

Further, in the present invention, the error caused by the influence of the tissue and other light-absorbing substances in blood is corrected by inputting a value measured by a blood sampling method into an apparatus, thereby improving the reliability of the subsequent measured value. Can be increased. That is, the gold standard for measuring the methemoglobin MetHb concentration ratio in blood is a blood sampling method using a carbon monoxide oximeter or the like. By calibrating using such reliable measurements,
The accuracy of the measured value can be improved.

As described above, the causes (2), (3) and (4) of the occurrence of methemoglobin MetHb in blood are caused by the action of treating patients with methemoglobin MetHb.
b) occurs, but if the calibration is performed before or during the treatment, it becomes possible to accurately and continuously monitor changes in blood methemoglobin MetHb concentration during the subsequent treatment process. The safety of the treatment can be greatly improved. In this case, providing a marker function such as a memory function, a trend display, and the start of oxygen inhalation in the device makes it easy for a patient with methemoglobin MetHbemia due to drug poisoning to be treated after being brought into a hospital. I do.

On the other hand, in the present invention, in a pulse oximeter using three wavelengths, the operator selects whether to measure methemoglobin MetHb or carboxyhemoglobin COHb, thereby selecting the measurement. Can be configured to measure the concentration of any selected substance using the formula:
For example, it is shown in the patent application (Japanese Patent Application No. 2000-366152) proposed by the present applicant that the concentration of carboxyhemoglobin COHb can be measured by selecting the wavelength of orange or red orange as the third wavelength. As described above, methemoglobin MetHb can be measured with the same combination of wavelengths under the condition that there is no carboxyhemoglobin COHb as described above.

That is, at an emergency site, a patient who is unconscious due to an accident such as a fire has a strong suspicion of carbon monoxide poisoning. Therefore, it is possible to selectively use the measurement of carboxyhemoglobin COHb. If it is known that the substance is poisoned by an aniline-based pesticide, it is possible to select the measurement of methemoglobin MetHb. The principle of the pulse oximeter is that if three wavelengths are used, it is possible to determine the concentration ratio of three or less blood light absorbing substances, but as in this case, if the concentration of a certain substance is 0, Assuming that the operator can select the substance to be measured, the calculation formula can be changed to use three wavelengths, and to obtain the concentration ratio of more than three blood light absorbing substances. Become.

Further, in the present invention, in a pulse oximeter using three wavelengths, methemoglobin Met is used.
It can be configured to indicate the presence of abnormal hemoglobin, either Hb or carboxyhemoglobin COHb. For example, if the first wavelength is 940n
m, the second wavelength is 660 nm, and the third wavelength is 621 nm, 100% oxygenated hemoglobin O2H in blood is selected.
From the condition of b, changes in the extinction ratios when only carboxyhemoglobin COHb increases and when only methemoglobin MetHb increases are represented by Φ13 and Φ12, respectively.
As shown in FIG. 9, even if the carboxyhemoglobin COHb increases or the methemoglobin MetHb increases, the extinction ratio Φ13 decreases as shown in FIG. That is, point A shown in FIG.
= 80%, carboxyhemoglobin COHb = 20%, or oxyhemoglobin O2 Hb = 95% and methemoglobin MetHb = 5%.

Therefore, as shown in FIG. 9, a threshold value is provided for the dimming ratio, and when the dimming ratio goes out of this threshold value, whether the carbon monoxide hemoglobin COHb or the methemoglobin MetHb is present. Can express, although not known, that any abnormal hemoglobin is present. In particular, when an unconscious patient is found at the emergency site, if it is found that there is abnormal hemoglobin, blood is immediately collected and carboxyhemoglobin C is collected.
By confirming whether it is OHb or methemoglobin MetHb, it is possible to carry out a quick and accurate treatment. During anesthesia, methemoglobin MetH is administered by local anesthesia or administration of a vasodilator.
It is also known that carbon monoxide hemoglobin COHb is rarely generated by the occurrence of b or the reaction of an inhaled anesthetic with a desiccant.

As described above, during anesthesia, although there is a possibility that methemoglobin MetHb or carboxyhemoglobin COHb may be unintentionally generated, the conventional pulse oximeter cannot detect them. However, according to the present invention, the occurrence of abnormal hemoglobin of methemoglobin MetHb or carboxyhemoglobin COHb can be continuously monitored during anesthesia, and an alarm can be displayed when these occur. Becomes Then, the anesthesiologist can detect the abnormality of the patient based on the alarm display, perform blood sampling, and confirm which abnormal hemoglobin has occurred, thereby enabling early treatment.

In the present invention, it is possible to obtain a calculation method by which the effect of the dye methylene blue, which is a therapeutic agent for methemoglobin MetHb blood, on methemoglobin MetHb measurement can be eliminated. That is, as a treatment for methemoglobin MetHb, intravenous administration of methylene blue is generally known. The peak value of the light absorption of this methylene blue is 668 nm, and when methylene blue is present in blood, appropriate measurement can be performed not only with a conventional pulse oximeter but also with a carbon monoxide oximeter using a wavelength around 660 nm. Disappears. For this reason, there is no method for continuously monitoring the therapeutic effect of decreasing methemoglobin MetHb during the treatment with methylene blue. Therefore, in the present invention, methemoglobin MetH using methylene blue is used.
b) It is possible to measure an appropriate blood methemoglobin MetHb concentration in which the influence of light absorption by methylene blue is removed during the treatment of blood disease.

[0037]

In order to achieve the above object, a hemoglobin concentration measuring apparatus according to the present invention comprises at least a near-infrared region as a first wavelength, a red region as a second wavelength, and a red-orange color as a third wavelength. A light source that emits three light wavelengths having different regions, light receiving means for receiving light emitted from the light source and transmitted or reflected by living tissue, and a light receiving output signal at each wavelength from the light receiving means due to pulsation of blood And a concentration ratio for calculating a concentration ratio of at least oxyhemoglobin and methemoglobin based on an output from the dimming ratio calculating unit based on the variation of the dimming ratio Φ between the wavelengths. Calculation means,
It is characterized by having.

In this case, the concentration ratio calculating means assumes that, when methylene blue is administered to the living tissue to treat methemoglobinemia, at least the concentrations of reduced hemoglobin and carboxyhemoglobin do not change. It can be configured to calculate the concentration ratio of oxidized hemoglobin, methemoglobin, and methylene blue.

Further, it is possible to further comprise an oxygen saturation calculating means for calculating the functional oxygen saturation or the fractional oxygen saturation based on the output of the concentration ratio calculating means.

Further, it is possible to comprise an alarm display means for displaying an alarm according to the level of the methemoglobin concentration ratio obtained by the concentration ratio calculation means.

An event input means for inputting an event at the time of event information relating to treatment of a patient, a time and event information input to the event input means, and a storage for storing a calculation result of the density ratio calculating means. Means can be further provided.

In this case, it is possible to have a display means for displaying the calculation result in a trend display and displaying the event information stored in the storage means on the trend display in accordance with the time.

In addition, an interface for transmitting the event information, the time, and the calculation result stored in the storage means to an external device may be provided.

The apparatus for measuring hemoglobin concentration according to the present invention comprises: a light source emitting a plurality of different light wavelengths; a light-receiving means for receiving light emitted from the light source and transmitted or reflected by living tissue; and at least one type of hemoglobin concentration. Calibration value input means for inputting a value, and dimming degree ratio calculating means for calculating a dimming degree ratio Φ between respective wavelengths based on fluctuations of a light receiving output signal at each wavelength from the light receiving means due to blood pulsation. And concentration calculating means for calculating the concentration of at least oxyhemoglobin, reduced hemoglobin and methemoglobin based on the output from the dimming degree ratio calculating means and the blood light absorbing substance concentration value input to the calibration value input means. .

There is also provided storage means for storing data relating to the dimming degree ratio Φ, using the data stored in the storage means and the blood light-absorbing substance concentration value input to the calibration value input means. It is also possible to include the concentration calculating means for retroactively recalculating at least oxyhemoglobin and methemoglobin.

On the other hand, the hemoglobin concentration measuring apparatus according to the present invention comprises a selecting means for instructing to calculate the methemoglobin concentration ratio, and instructing the calculating means to calculate the methemoglobin concentration ratio. In a state where the light is not present, the concentration ratio calculating means outputs a light-receiving output signal output by receiving, by the light-receiving means, light transmitted or reflected by at least two different wavelengths of light emitted from the light source through the living tissue. On the basis of the fluctuation, at least the concentration ratio of oxyhemoglobin is calculated, and in a state in which the selection unit is instructing to calculate the concentration ratio of methemoglobin, the concentration ratio calculation unit is emitted by the light source. At least three different wavelengths of light transmitted or reflected by the living tissue are received by the light receiving means and output. Was based on the change of the light reception output signals,
It can be configured to calculate at least the concentration ratio of oxyhemoglobin and methemoglobin.

Further, the hemoglobin concentration measuring device according to the present invention comprises: a light source emitting a plurality of different light wavelengths; a light receiving means for receiving light emitted from the light source and transmitted or reflected by a living tissue; And a dimming ratio calculating unit for calculating a dimming ratio Φ between the respective wavelengths based on the variation of the light receiving output signal at each wavelength from the light receiving unit, and at least based on an output from the dimming ratio calculating unit. Concentration ratio calculating means for calculating the concentration ratio of oxyhemoglobin, reduced hemoglobin, and methemoglobin, and display means for displaying a hemoglobin value measured by a method of calibrating the oxyhemoglobin, reduced hemoglobin, and methemoglobin in two-dimensional coordinates, Configuration.

In the above-mentioned hemoglobin concentration measuring device, the light source emits at least three different light wavelengths of a near-infrared region as a first wavelength, a red region as a second wavelength, and a red-orange region as a third wavelength. Can be configured.

Further, the hemoglobin concentration measuring apparatus according to the present invention has a near-infrared region as at least the first wavelength,
A light source that emits three different wavelengths of light in a red region as a second wavelength and a red-orange region as a third wavelength; a light receiving unit that receives light emitted from the light source and transmitted or reflected through a living tissue; And a dimming ratio calculating unit for calculating a dimming ratio Φ between the respective wavelengths based on the variation of the light receiving output signal at each wavelength from the light receiving unit, and at least based on an output from the dimming ratio calculating unit. Concentration ratio calculating means for calculating the concentration ratio of oxyhemoglobin, carboxyhemoglobin and methemoglobin; and switching means for selecting the concentration ratio calculating means for calculating the concentration ratio between carboxyhemoglobin and methemoglobin. And characterized in that:

In this case, the extinction ratio calculating means:
A configuration in which a predetermined threshold value is set for the calculated dimming ratio, and a display unit is provided for displaying an alarm when the calculated dimming ratio for the hemoglobin switched by the switching unit exceeds the range of the threshold value. It can be.

The apparatus for measuring the concentration of hemoglobin according to the present invention uses the near-infrared region and the second
A light source that emits three different light wavelengths of a red region as a wavelength and a red-orange region as a third wavelength, light receiving means for receiving light transmitted from or reflected by living tissue emitted from the light source, and light pulsation caused by blood pulsation A dimming intensity ratio calculating unit that calculates a concentration ratio of carboxyhemoglobin and methemoglobin based on a variation of a light receiving output signal at each wavelength from the light receiving unit; A predetermined threshold value for carboxyhemoglobin and for methemoglobin is set to the light intensity ratio, and the calculated dimming ratio of at least one of carboxyhemoglobin and methemoglobin exceeds the range of the threshold value. Display means for displaying an alarm.

In the present invention, at least the near-infrared region of 790 to 1000 nm as the first wavelength, the second wavelength
It is preferable to set the wavelength to a red region of 640 to 675 nm and the third wavelength to a red-orange region of 590 to 660 nm, and it is more preferable to set the third wavelength to 621 nm.

Further, the hemoglobin concentration measuring device according to the present invention inputs a light source emitting a plurality of different light wavelengths, a light receiving means for receiving light emitted from the light source and transmitted or reflected through a living tissue, and a reference time point. Input means for
Dimming intensity ratio calculating means for calculating a dimming intensity ratio Φ between the respective wavelengths based on the fluctuation of the received light output signal at each wavelength from the light receiving unit due to blood pulsation; and at least carboxyhemoglobin and methemoglobin A density value variation calculating means for calculating a density value variation from a reference time point based on the density at the reference time point input by the input means for any one of the density values. Can be. This allows the input means to:
As a reference point in time, for example, a doctor performing treatment performs an input operation for recognizing a treatment start time, and at least carboxyhemoglobin and methemoglobin after the treatment start time based on the concentration at the treatment start time It is possible to calculate any one density value variation.

Further, the input means is a calibration value input means for inputting a blood light absorbing substance concentration value, and the concentration value variation calculating means inputs a temporary value as a blood light absorbing substance concentration value to the calibration value input means. By inputting, it is possible to configure so as to calculate the density value variation after the reference time. Thereby, as a reference time point, for example, assuming a treatment start time point,
At the start of the treatment, by inputting the provisional values as the concentration values of carboxyhemoglobin and methemoglobin into the calibration value input means, at least the variation of the concentration value of carboxyhemoglobin or methemoglobin after the start of the treatment. Can be calculated.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a hemoglobin concentration measuring device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram showing the structure of a hemoglobin concentration measuring apparatus according to the present invention. That is, in FIG. 1, reference numerals 1, 2, and 3 indicate light emitting elements as light sources, and these light emitting elements 1, 2, and 3
Are elements that emit light of wavelengths λ1 (for example, near infrared region of 790 to 1000 nm), λ2 (for example, red region of 640 to 675 nm), and λ3 (for example, orange or red-orange region of 590 to 660 nm). It is configured to be driven by the drive circuit 4. Light emitted from these light emitting elements 1, 2, and 3 passes through the living tissue 5 and is received by the light receiving element 6 as a receiving unit, and is converted into an electric signal. Then, these converted signals are amplified by the amplifier 7 and distributed to the filters 9, 10 and 11 corresponding to the respective optical wavelengths by the multiplexer 8.

In this way, the filters 9, 10,.
The signals of the wavelengths respectively distributed to 11 are filtered by filters 9, 10 and 11 to remove high-frequency components, which are noises, and then converted to digital signals by an A / D converter 12.
Logarithmic calculation circuit 14, Φ calculation circuit 15 as dimming degree comparison calculating means for calculating dimming degree ratio Φ, and hemoglobin Hb
The signals are sequentially input to an Hb concentration calculating circuit 16 as a concentration calculating means. Reference numeral 13 denotes a timing control circuit. The timing control circuit 13 sends necessary timing signals to the drive circuit 4, the multiplexer 8, and the A / D converter 12 to operate them. Is controlled.

In the logarithmic calculation circuit 14, the logarithms lnI1, lnI2, and lnI3 of the outputs I1, I2, and I3 of the A / D converter 12 are obtained. In the Φ calculation circuit 15, the logarithms lnI1, lnI2, ln obtained by the logarithmic calculation circuit 14 are used.
The pulsation component is extracted from I3, and Φ12 = ΔlnI1 / Δl
Calculate nI2, .PHI.13 = .DELTA.lnI1 / .DELTA.lnI3.
Then, in the hemoglobin Hb concentration calculating circuit 16, a simultaneous equation is solved from two formulas representing Φ,
Oxygenated hemoglobin O2 Hb, reduced hemoglobin RHb,
The concentration ratio of methemoglobin MetHb is determined.

The calculation formula in the hemoglobin Hb concentration calculation circuit 16 is as follows.

[0060]

(Equation 4)

In the above formula, RHb is the concentration ratio of reduced hemoglobin, O 2 Hb is the concentration ratio of oxyhemoglobin, M
etHb indicates the concentration ratio of methemoglobin. Eoi (i = 1,
2,3) is the extinction coefficient of oxyhemoglobin O2 Hb, Eri (i
= 1,2,3) is the extinction coefficient of reduced hemoglobin RHb, Emi
(I = 1,2,3) is the extinction coefficient of methemoglobin MetHb,
Fi indicates a scattering coefficient, and i = 1, 2, and 3 indicate light wavelengths λ1,
λ2 and λ3 are shown. In this case, the Eoi, Eri, Eci,
Since Fi is a known value, Φ12 = ΔA1 //
When ΔA2 and Φ13 = ΔA1 / ΔA3 are measured and substituted into the above equation to solve the simultaneous equations, oxyhemoglobin O2 Hb
, Reduced hemoglobin RHb, methemoglobin MetHb
Can be determined.

The method of determining the concentration ratio of oxyhemoglobin O 2 Hb, reduced hemoglobin RHb, and methemoglobin MetHb from Φ12 and Φ13 is not calculated by simultaneous equations, but is prepared in advance by calculation or based on experimental results. Alternatively, a method of referring to the table may be used.

The signal relating to the concentration ratio of oxyhemoglobin O2 Hb, reduced hemoglobin RHb, and methemoglobin MetHb calculated by the hemoglobin Hb concentration calculation circuit 16 based on the above-described calculation method is used as the Hb concentration display means as the hemoglobin Hb concentration display means. The data is sent to a monitor 17, a trend display 18 as a trend display, a storage circuit 19 as a storage, and an alarm circuit 20 as an alarm display. In this case, in the Hb concentration indicator 17, as shown in FIGS.
Arterial oxygen saturation (SpO2) and methemoglobin Met
The Hb concentration is displayed.

FIG. 2 shows an example of the configuration of the Hb concentration indicator 17. In the configuration example shown in FIG. 2, Sp having functional oxygen saturation is used.
O2 [%] = O2 Hb / (O2 Hb + RHb) [%] or SpO2 [%] consisting of fractional oxygen saturation = O2 Hb / (O2 Hb + RHb + Met)
Hb) [%] is displayed by the functional / fractional display selection switching circuit 23 (see FIG. 1) in the selected method. That is, in this case, the numerical value display unit 30 for SpO2 [%] and the numerical value display unit 3 for MetHb concentration [%]
1 and a numerical display 30 for the SpO2 [%].
For the above, a functional selection switch / selection state display unit 34 and a fractional selection switch / selection state display unit 34 for performing a switching operation for selecting the above-mentioned Functional or Fractional and displaying the same, respectively. 35 are provided.

Further, the numerical value display section 3 of the SpO 2 [%]
The numerical value displayed as 0 is either a value obtained from three wavelengths or a value calculated from two wavelengths of red and near-infrared as in the conventional case.
(See FIG. 1), each can be displayed in a selected way. Then, the selected display in this case is performed by the MetHb measurement button 36. The MetHb measurement button 36 can be turned on to measure the concentration of various hemoglobins including methemoglobin at three wavelengths, and can be conventionally turned off at two wavelengths by turning it off. It is set so that the oxygen saturation (SpO2) can be measured by a method.

FIG. 3 shows another example of the structure of the Hb concentration indicator 17. As shown in FIG. In the configuration example shown in FIG.
The fractional SpO2 [%] is displayed on the numerical value display section 30 and the MetHb concentration [%] is displayed on the risk level display section 32 in which three risk levels are set. The risk level is effective even if it is set in two stages. Other configurations are the same as those shown in FIG. 2, and the same components are denoted by the same reference characters, and detailed description thereof will be omitted.

FIG. 4 shows still another example of the configuration of the Hb concentration indicator 17. As shown in FIG. In the configuration example shown in FIG. 4, with respect to the MetHb concentration [%], the risk level display unit 3 numerically displays the settings of the risk levels shown in FIG.
3 is displayed. Other configurations are the same as those shown in FIG. 2, and the same components are denoted by the same reference characters, and detailed description thereof will be omitted.

FIGS. 5 (a) and 5 (b) show an example of the configuration of the Hb concentration display 17 for performing another display. In the configuration example shown in FIG. 5A, the horizontal axis indicates the methemoglobin concentration, the vertical axis indicates the fractional oxygen saturation (oxyhemoglobin concentration), and the inclined axis indicates the reduced hemoglobin concentration. According to this display method, these three types of densities can be visually grasped simultaneously. Here, for example, point A in FIG. 5A indicates a methemoglobin concentration of 10%, a fractional oxygen saturation (oxyhemoglobin concentration) of 85%, and a reduced hemoglobin concentration of 5%. FIG. 5B shows a configuration example for performing another display. In this case, the horizontal axis indicates the methemoglobin concentration, the vertical axis indicates the reduced hemoglobin concentration, and the inclined axis indicates the fractional oxygen saturation (oxyhemoglobin concentration).
At the same time, it can be grasped visually.

On the other hand, in FIG.
When the methemoglobin MetHb concentration is higher than the value set by the alarm setting circuit 25, an alarm is generated by light, sound or message. The light can be displayed by turning on an alarm lamp, blinking a MetHb concentration danger level display lamp, blinking a MetHb concentration [%] display, and the like. Also, the sound display is
The presence of MetHb can be displayed as an alarm sound. In this case, it is possible to notify the density by changing the volume or the pitch according to the MetHb density. The variable volume or pitch can be a continuous expression according to the density or a discrete expression according to the risk level. In addition, the synchronization sound of the pulse wave can be changed according to the MetHb concentration. In this case, it is possible to adopt a method of changing the sound quality or changing the duration of sound generation depending on the presence of MetHb. In FIG. 1, reference numeral 26 denotes a clock circuit for causing the storage circuit 19 to perform a clock operation.

FIGS. 6A and 6B show SpO2 [%].
FIG. 3 shows an example of a display configuration of a trend display 18 for displaying a trend and a MetHb concentration [%] on a liquid crystal display or the like. In this case, for example, for a patient with methemoglobinemia due to drug poisoning, events such as oxygen inhalation, arrival at a hospital, blood sampling for calibration, MB (methylene blue) administration start, MB administration end, and the like are generated as event information related to patient treatment. In this case, the event input is performed by the event input circuit 21 (see FIG. 1) so that the input event information is displayed on the screen of the trend display 18. Then, as described above, the concentration ratio of oxyhemoglobin O2 Hb, reduced hemoglobin RHb, and methemoglobin MetHb calculated by the Hb concentration calculation circuit 16 and the event information are sent to the storage circuit 19 and stored. In this way, the data stored in the storage circuit 19 is retained even when the power is turned off, and can be reproduced and displayed on the trend display 18.

Note that, for example, as shown in FIG.
The trend of each hemoglobin concentration is functional,
Any concentration of fractional oxygen saturation (SpO2) can be displayed as a trend. Further, as shown in FIG. 6B, for each concentration of oxyhemoglobin O2 Hb, reduced hemoglobin RHb, and methemoglobin MetHb, the ratio of each concentration is trend-displayed together with the event information, with the whole being 100%. Can be. The data stored in the storage circuit 19 is configured to be transmitted to an external device such as a personal computer via an external interface (see FIG. 1).

In the apparatus configuration shown in FIG. 1, a calibration value input circuit 22 for inputting the concentration of a light-absorbing substance in blood measured by a blood sampling method is provided. The data input to the calibration value input circuit 22 is sent to the Hb concentration calculation circuit 16. Then, the Hb concentration calculation circuit 16 performs calibration calculation of oxyhemoglobin O2 Hb, reduced hemoglobin RHb, and methemoglobin MetHb based on the input values. This calibration calculation can be performed as follows.

First, when a change in the dimming degree due to the pulsation of the living tissue caused by the pulsation of the blood is considered, the ratio Φ of the dimming degree is expressed by the following equation (see Japanese Patent Application Laid-Open No. 8-322822).

[0074]

(Equation 5)

Here, EX is a term indicating the dimming caused by the pulsation of the living tissue, and is an unknown number.

In this way, the unknown EX can be determined by substituting the value obtained by collecting blood and measuring it into the above equation. Thereafter, by using a simultaneous equation including the determined unknown EX, it is possible to obtain a highly accurate measurement result in consideration of the pulsation of the living tissue.

Further, the data of the respective dimming ratios Φ or the respective hemoglobin concentration ratios stored in the storage circuit 19 before the input of the calibration values is recalculated using the blood light-absorbing substance concentration values measured by collecting blood. A highly accurate measurement result can be obtained retroactively. Furthermore, instead of inputting the concentration value obtained by blood collection as a calibration value, a treatment start time such as nitric oxide (NO) administration or vasodilator administration for vasodilation therapy, and a local anesthetic administration start time Or at the start of inhalation anesthesia, the carboxyhemoglobin (COHb) and / or methemoglobin (M
By inputting a temporary value (for example, zero) as the calibration value of etHb), carboxyhemoglobin (COHb) and / or methemoglobin (MetH) after the start of the treatment can be obtained.
The variation in b) (mainly the increase due to administration) can be measured.

Since it is known that inhalation anesthesia using a desiccant generates carboxyhemoglobin in the body, the amount of carboxyhemoglobin generated in the body based on the start of inhalation anesthesia is known. It is useful to measure the increase. Also, instead of providing the calibration value input circuit, an input circuit for notifying the start time of treatment (may be a time point before the start of treatment) may be provided, and carboxyhemoglobin (COHb) and / or The fluctuation of methemoglobin (MetHb) can be measured.

As another calibration example, there is a case where errors due to other blood light absorbing substances such as carboxyhemoglobin and bilirubin are calibrated. That is, the calculation formula in consideration of carboxyhemoglobin COHb is as follows.

[0080]

(Equation 6)

Here, the measured O 2 Hb, RHb, Met
By substituting Hb and COHb into the above equation, the unknown EX can be obtained. Then, the obtained unknown number EX and the MetHb measured by the blood sampling method are substituted into the above equation.
Assuming that X and COHb are constant, the simultaneous equations can be solved to determine the concentration ratio of O2Hb, RHb, and MetHb. In the above equation, a term of bilirubin is provided, and it is also possible to calculate by substituting a bilirubin value measured by a blood sampling method, and it is also possible to apply other blood absorbing substances.

FIG. 7 shows another embodiment of the hemoglobin concentration measuring apparatus according to the present invention.
This shows a configuration example of the Hb concentration display 17 'corresponding to the concentration display 17. That is, in the Hb concentration indicator 17 of this embodiment, the measurement of methemoglobin MetHb or carboxyhemoglobin COHb is measured by M
By selectively operating the etHb measurement button 36 or the COHb measurement button 37, the COHb / MetH shown in FIG.
The measurement switching circuit 27 allows the Hb concentration calculation circuit 16 to calculate the methemoglobin MetHb concentration described above (see Equations 4 and 5) or carboxyhemoglobin C
Select and apply the formula for calculating the OHb concentration,
The b concentration or COHb concentration [%] is calculated. Then, the calculated MetHb concentration or COHb concentration is
The OHb / MetHb concentration [%] can be displayed on the numerical value display section 31 '.

The other configuration and operation are the same as those of the configuration example shown in FIG. 2 described above, and the same components are denoted by the same reference characters, and detailed description thereof will not be repeated.
Note that regarding the measurement of carboxyhemoglobin COHb,
The calculation formula is described in the patent application previously proposed by the present applicant (US Patent Application No. USSN.09 / 725865).
And as described above, methemoglobin MetHb described above.
This can be achieved by replacing the coefficients for methemoglobin MetHb with the coefficients for carboxyhemoglobin COHb in the equation for calculating the concentration (see Equations 4 and 5).

Further, when the calculated dimming ratio of the selected hemoglobin of the MetHb measurement button 36 or the COHb measurement button 37 exceeds the predetermined threshold range, an alarm such as a sound is issued. Alternatively, a configuration may be adopted in which a risk level display unit that displays the risk levels as shown in FIGS. 3 and 4 is provided and displayed.

FIG. 8 shows the Hb concentration indicator 1 shown in FIG.
This shows another example of the configuration of 7 ', which corresponds to the above-described Hb concentration indicator 17 shown in FIG. That is, in the Hb concentration indicator 17 of this embodiment, an alarm ON / OFF switch 38 for selecting ON / OFF operation for the abnormal hemoglobin detection function, and a risk level for selectively setting a risk level for generating an alarm A selection switch 39 is provided. In this case, when the alarm ON / OFF switch 38 is turned on, the methemoglobin M larger than a preset level is set.
Detecting a possible etHb concentration or carboxyhemoglobin COHb concentration generates the required alarm. The set level for generating the alarm is expressed by a combination of COHb / MetHb.
[O2 Hb = 50%, COHb = 50%]
The condition of [O2 Hb = 80%, MetHb = 20%] shows the same dimming ratio, so that the alarm setting level is, for example, COHb / MetHb = 50/20 (%), 3
A risk level display unit 3 that selects and sets the risk level selection switch 39, such as 5/10 (%) or 20/5 (%), and numerically displays the setting of the selected risk level.
3 '. Other configurations and operations are the same as those of the configuration example shown in FIG. 4 described above, and the same components are denoted by the same reference characters and detailed description thereof will not be repeated.

Next, the calibration calculation in the case of administering methylene blue to a methemoglobin MetHb blood patient will be described. As described above, the equation for calculating the concentration of methemoglobin MetHb from three wavelengths is as shown in equation (2). Here, the calculation formula when the pulse oximeter is calibrated by measuring with a carbon monoxide oximeter immediately before administering methylene blue is as shown in the above [Equation 6]. Therefore, in the above formula (6), assuming that reduced hemoglobin RHb, carboxyhemoglobin COHb, and unknown EX do not change during treatment with methylene blue, and substituting the values at the time of calibration, the variable becomes Oxygenated hemoglobin O2 Hb and methemoglobin MetHb are included. Here, when methylene blue enters, it becomes as shown in the following equation.

[0087]

(Equation 7)

If it is known that the patient is not inhaling carbon monoxide, there is no need to measure with a carbon monoxide oximeter, and there is no need to calibrate the pulse oximeter. When a calculation method that does not consider the unknown number EX is adopted, EX =
A calculation formula with 0 may be used. The same applies to the following equations.

In this case, Edi indicates the extinction coefficient of methylene blue, i = 1, 2, 3 indicates the light wavelengths λ1, λ2, λ3, and Cd indicates the blood methylene blue concentration. In this case, assuming that RHb, COHb, and EX do not change, and substituting the value at the time of calibration, the variable becomes O2 Hb.
And MetHb and Cd. Since there are two calculation equations, it is possible to obtain the concentration ratios of the three variables O2 Hb, MetHb and Cd by solving the simultaneous equations. That is, the concentration ratio between O2 Hb and MetHb can be determined, and methemoglobin MetHb can be obtained.
, It is possible to continuously monitor the therapeutic effect of decreasing. In actual treatment of methemoglobin MetHb, 100% oxygen O2 is usually inhaled due to reduced oxygen carrying capacity of blood, so that reduced hemoglobin RHb of arterial blood is close to 0 and carboxyhemoglobin C
Since OHb is hardly kept at a high concentration,
The assumption that RHb and COHb remain nearly zero during treatment with methylene blue is sufficiently practical. Therefore, as an actual operation of the apparatus, a switch indicating the administration of methylene blue is provided, and by operating this switch, the calibration calculation can be performed thereafter by a calculation formula in which RHb and COHb are fixed as constants.

The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and many design changes can be made without departing from the spirit of the present invention.

[0091]

As is clear from the above-described embodiment, according to the hemoglobin concentration measuring apparatus according to the present invention, at least the near-infrared region as the first wavelength, the red region as the second wavelength, and the red-orange region as the third wavelength. A light source emitting three different light wavelengths, light receiving means for receiving light transmitted from or reflected by living tissue emitted from the light source, and a light receiving output signal at each wavelength from the light receiving means due to blood pulsation. A dimming ratio calculating unit that calculates a dimming ratio Φ between the wavelengths based on the fluctuation; and a concentration ratio of at least oxyhemoglobin, reduced hemoglobin, and methemoglobin based on an output from the dimming ratio calculating unit. With the configuration including the concentration ratio calculating means, a change in transmitted light due to a change in methemoglobin MetHb can be reduced by S / H.
In addition to detection in a state of good N ratio, methemoglobin M
facilitates discrimination between etHb and reduced hemoglobin RHb,
An appropriate measurement of methemoglobin MetHb can be performed.

In the measuring apparatus of the present invention, the measurement using two wavelengths is less affected by the pulsation of the tissue than the measurement using three wavelengths. Therefore, for a patient who is not suspected of carbon monoxide poisoning, “MetHb” is used. By turning off the measurement button 36 ", the oxygen saturation (SpO2) can be measured at the two wavelengths by a conventional method. On the other hand, for patients suspected of drug addiction, "MetHb
By turning on the measurement button 36 ", it is possible to measure the concentration of various hemoglobins including methemoglobin at three wavelengths. Also, without displaying the accurate methemoglobin concentration in the unit of 1%, the methemoglobin concentration can be measured. By displaying the presence of hemoglobin and the danger level, rescue workers can determine whether patients should be transported to hospitals equipped with hyperbaric oxygen therapy equipment or methylene blue therapy equipment, and medical staff can formulate treatment policies. Furthermore, by using the concentration value of the light-absorbing substance in blood measured by the blood sampling method as a calibration value, it is possible to more accurately measure the concentration of each hemoglobin.

However, in the present invention, the most accurate method for measuring the methemoglobin MetHb concentration in blood is the carbon monoxide oximeter (CO-Oximeter).
) Is based on the measurement of the blood sampling method. By calibrating using such highly reliable measurement values, the accuracy of the measurement values can be improved. In general, treatment of acute drug poisoning is performed by oxygen inhalation and methylene blue administration. In such treatment, it is possible to monitor the process of reducing the methemoglobin MetHb concentration with high reliability. Becomes

Further, in the measuring apparatus of the present invention, the values of methemoglobin concentration, reduced hemoglobin concentration, and fractional oxygen saturation (oxyhemoglobin concentration) can be visually grasped simultaneously in three dimensions by two-dimensional coordinates. Can be.

Further, in the measuring apparatus of the present invention, the change of each hemoglobin concentration with the passage of time can be confirmed together with an event marker or the like relating to the treatment of a patient, so that it becomes important data for setting a guideline of treatment. ,
In addition, there is an advantage that the treatment effect can be visually confirmed.

On the other hand, in the measuring device of the present invention, whether to measure methemoglobin MetHb or carboxyhemoglobin COHb is selected by selecting
The selected measurement formula can be used to determine the concentration of any selected substance. Moreover, in this case, it can be configured to indicate that abnormal hemoglobin of either methemoglobin MetHb or carboxyhemoglobin COHb is present. With this configuration, when an unconscious patient is found at the emergency site, if it is found that there is abnormal hemoglobin, blood is collected immediately and carboxyhemoglobin COHb or methemoglobin MetHb is obtained. By confirming this, it is possible to perform an accurate and prompt treatment. In addition, the apparatus of the present invention makes it possible to measure the appropriate concentration of methemoglobin MetHb in blood, eliminating the effect of light absorption by methylene blue, during treatment of methemoglobin MetHb with methylene blue.

Further, the hemoglobin concentration measuring apparatus according to the present invention further comprises an input means for inputting a reference time point, and at least one of the concentrations of carboxyhemoglobin and methemoglobin is input by the input means. There may be provided a density value variation calculating means for calculating a density value variation after the reference time based on the input density at the reference time. Thus, the input means is operated by a treating doctor or the like as a reference time point, for example, to recognize the treatment start time, so that at least monoxide oxidation after the treatment start time based on the concentration at the treatment start time is performed. It is possible to calculate the concentration value variation of any one of carbon hemoglobin and methemoglobin.

Further, the input means is a calibration value input means for inputting a blood light absorbing substance concentration value, and the concentration value variation calculating means inputs a temporary value as a blood light absorbing substance concentration value to the calibration value input means. By inputting, it is possible to configure so as to calculate the density value variation after the reference time. Thereby, as a reference time, for example, if the treatment start time, when starting treatment, by inputting a temporary value as a concentration value of carboxyhemoglobin or methemoglobin to the calibration value input means, after the treatment start time It is possible to calculate the variation of the concentration value of carboxyhemoglobin or methemoglobin.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a device configuration showing an embodiment of a hemoglobin concentration measuring device according to the present invention.

FIG. 2 is an explanatory diagram showing one configuration example of a hemoglobin Hb concentration indicator in FIG. 1;

FIG. 3 is an explanatory diagram showing another configuration example of the hemoglobin Hb concentration indicator shown in FIG. 2;

FIG. 4 is an explanatory view showing still another configuration example of the hemoglobin Hb concentration indicator shown in FIG. 2;

5 (a) and 5 (b) show hemoglobin H in FIG.
b It is explanatory drawing which shows each different example of a structure which performs another display of a density display.

6 (a) and 6 (b) are explanatory diagrams showing configuration examples for performing different displays on the trend display device in FIG. 1. FIG.

FIG. 7 is an explanatory diagram showing a configuration example of a hemoglobin Hb concentration indicator in another embodiment of the hemoglobin concentration measuring device according to the present invention.

FIG. 8 is an explanatory diagram showing another example of the configuration of the hemoglobin Hb concentration indicator shown in FIG. 7;

FIG. 9 is a characteristic diagram showing a relationship between two extinction ratios Φ12 and Φ13 at a light wavelength applied to the hemoglobin concentration measuring device according to the present invention.

FIG. 10 is a characteristic diagram showing a relationship between two extinction ratios Φ12 and Φ13 in the hemoglobin concentration measuring device when a third wavelength of 805 nm of near infrared is set.

FIG. 11 is a characteristic curve diagram showing a relationship between a light wavelength and an absorption coefficient applied to the present invention.

[Description of Signs] 1, 2, 3 Light-emitting element 4 Drive circuit 5 Living tissue 6 Light-receiving element 7 Amplifier 8 Multiplexer 9, 10, 11 Filter 12 A / D converter 13 Timing control circuit 14 Logarithmic calculation circuit 15 Φ calculation circuit 16 Hb concentration calculation circuit 17 Hb concentration display 17 ′ Hb concentration display 18 trend display 19 storage circuit 20 alarm circuit 21 event input circuit 22 calibration value input circuit 23 Functional / Fractional display selection switching circuit 24 2 wavelength / 3 wavelength calculation Display selection switching circuit 25 Alarm setting circuit 26 Clock circuit 27 COHb / MetHb measurement switching circuit 30 Numerical display of SpO2 [%] 31 Numerical display of MetHb concentration [%] 31 'Numerical display of COHb / MetHb concentration [%] 32, 33 MetHb concentration [%] risk level indicator 33 'COHb / MetHb Degrees (%) risk level display section 34 Functional selection switching switch / selection state display unit 35 Fractional selected selector switch / selection state display unit 36 MetHb measurement button 37 COHb measurement button 38 alarm ON / OFF switch 39 risk level selection switch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Rio Kanemoto 1-31-4 Nishi-Ochiai, Shinjuku-ku, Tokyo Inside Japan Optoelectronics Co., Ltd. No. 4 Inside Nihon Koden Kogyo Co., Ltd. (72) Inventor Teiji Ugawa 1-31-4 Nishi-Ochiai Shinjuku-ku, Tokyo F-term in Nihon Koden Kogyo Co., Ltd. (reference) 2G059 AA01 AA06 BB12 BB13 CC04 CC07 CC18 EE01 EE06 EE11 FF06 FF10 GG02 GG03 GG07 HH01 HH02 HH06 KK01 MM01 MM05 MM10 MM14 NN10 PP02 PP04 4C038 KK01 KL05 KL07 KM01 KX01 KX02 KY03 KY04

Claims (19)

[Claims] 1. a near-infrared region as at least a first wavelength;
A light source that emits three different wavelengths of light in a red region as a second wavelength and a red-orange region as a third wavelength; a light receiving unit that receives light emitted from the light source and transmitted or reflected through living tissue; And a dimming intensity ratio calculating means for calculating a dimming intensity ratio Φ between the respective wavelengths based on the fluctuation of the light receiving output signal at each wavelength from the light receiving device, and at least based on an output from the dimming intensity ratio calculating device. A concentration ratio calculating means for calculating a concentration ratio of oxyhemoglobin and methemoglobin. 2. The method of claim 2, wherein the concentration ratio calculating means assumes that at least the concentrations of reduced hemoglobin and carboxyhemoglobin do not change when methemoglobinemia is treated by administering methylene blue to the living tissue. 2. The hemoglobin concentration measuring device according to claim 1, wherein the hemoglobin concentration measuring device is configured to calculate a concentration ratio between oxidized hemoglobin, methemoglobin, and methylene blue. 3. A light source that emits a plurality of different light wavelengths; a light receiving unit that receives light transmitted from or reflected by living tissue emitted from the light source; and a light receiving unit that receives light from the light receiving unit due to blood pulsation. A dimming ratio calculating means for calculating a dimming ratio Φ between the wavelengths based on the variation of the received light output signal; and at least the concentrations of oxyhemoglobin, reduced hemoglobin and methemoglobin based on the output from the dimming ratio calculating means. A hemoglobin comprising: a concentration ratio calculating means for calculating a ratio; and an oxygen saturation calculating means for calculating a functional oxygen saturation or a fractional oxygen saturation based on an output of the concentration ratio calculating means. Concentration measuring device. 4. A light source that emits a plurality of different light wavelengths; a light receiving unit that receives light transmitted from or reflected by living tissue emitted from the light source; and a light receiving unit that receives light from the light receiving unit due to blood pulsation. A dimming ratio calculating unit that calculates a dimming ratio Φ between the wavelengths based on the fluctuation of the received light output signal; and calculating at least a concentration ratio of oxyhemoglobin and methemoglobin based on an output from the dimming ratio calculating unit. A hemoglobin concentration measuring device, comprising: a concentration ratio calculating means for performing the measurement; and an alarm display means for displaying an alarm according to the level of the concentration ratio of methemoglobin obtained by the concentration ratio calculating means. 5. A light source that emits a plurality of different light wavelengths, a light receiving unit that receives light transmitted from or reflected by living tissue emitted from the light source, and a light receiving unit that receives light from the light receiving unit due to blood pulsation. A dimming ratio calculating unit that calculates a dimming ratio Φ between the wavelengths based on the fluctuation of the received light output signal; and calculating at least a concentration ratio of oxyhemoglobin and methemoglobin based on an output from the dimming ratio calculating unit. Density ratio calculating means, an event input means for inputting an event when event information relating to treatment of a patient is provided, time and event information input to the event input means, and a calculation result of the density ratio calculating means. A hemoglobin concentration measuring device comprising: 6. The display device according to claim 5, further comprising display means for trend-displaying the calculation result, and displaying the event information stored by the storage means on the trend display in accordance with the time. The hemoglobin concentration measuring device according to the above. 7. The hemoglobin concentration measuring device according to claim 5, further comprising an interface for transmitting the event information, the time, and the calculation result stored in the storage means to an external device. 8. A light source that emits a plurality of different light wavelengths, light receiving means for receiving light emitted from the light source and transmitted or reflected through a living tissue, and a calibration value input for inputting at least one blood light absorbing substance concentration value Means for calculating an extinction ratio Φ between respective wavelengths based on a variation of a light reception output signal at each wavelength from the light receiving unit due to blood pulsation; and the extinction ratio calculation Concentration calculating means for calculating at least the concentrations of oxyhemoglobin and methemoglobin based on the output from the means and the blood light-absorbing substance concentration value input to the calibration value input means. measuring device. 9. A light source that emits a plurality of different light wavelengths, a light receiving unit that receives light transmitted from or reflected by living tissue emitted from the light source, and a light source that emits light at each wavelength from the light receiving unit due to pulsation of blood. A dimming intensity ratio calculating means for calculating a dimming intensity ratio Φ between respective wavelengths based on the fluctuation of the received light output signal; Concentration ratio calculating means, and selecting means for instructing to calculate the concentration ratio of methemoglobin, wherein in the state where the selecting means does not instruct to calculate the concentration ratio of methemoglobin, the concentration The ratio calculating means receives, by the light receiving means, light having at least two different wavelengths of light emitted by the light source transmitted or reflected by a living tissue. The calculated concentration ratio of oxyhemoglobin is calculated at least based on the fluctuation of the received light output signal output by the above-described method. In the state where the selecting means indicates that the concentration ratio of methemoglobin is calculated, the concentration ratio calculation is performed. The means includes at least oxyhemoglobin and methaemoglobin based on a change in a light reception output signal output by receiving, by the light receiving means, light transmitted or reflected by at least three different wavelengths of light emitted by the light source through a living tissue. A hemoglobin concentration measuring device for calculating a concentration ratio of hemoglobin. 10. A light source that emits a plurality of different light wavelengths; a light receiving unit that receives light transmitted from or reflected by living tissue emitted from the light source; and a light receiving unit that receives light from the light receiving unit due to blood pulsation. A dimming ratio calculating means for calculating a dimming ratio Φ between the wavelengths based on the variation of the received light output signal; and at least the concentrations of oxyhemoglobin, reduced hemoglobin and methemoglobin based on the output from the dimming ratio calculating means. A hemoglobin concentration measuring device comprising: a concentration ratio calculating means for calculating a ratio; and a display means for displaying a hemoglobin value measured by a method of grading oxyhemoglobin, reduced hemoglobin, and methemoglobin in two-dimensional coordinates. 11. The light source is configured to emit at least three different light wavelengths in a near-infrared region as a first wavelength, a red region as a second wavelength, and a red-orange region as a third wavelength. The hemoglobin concentration measuring device according to the above. 12. A light source which emits at least three different wavelengths of light in a near-infrared region as a first wavelength, a red region as a second wavelength, and a red-orange region as a third wavelength; A light receiving means for receiving the reflected light; and a light reduction ratio calculating means for calculating a light reduction ratio Φ between the respective wavelengths based on a change in a light receiving output signal at each wavelength from the light receiving unit due to the pulsation of blood. Concentration concentration calculating means for calculating at least the concentration ratio of oxyhemoglobin, carboxyhemoglobin and methemoglobin based on the output from the dimming degree ratio calculating means; and carboxyhemoglobin and methemoglobin for the concentration ratio calculating means. A switching unit for selectively performing a calculation of a concentration ratio with hemoglobin; and a hemoglobin concentration measuring device. 13. A predetermined threshold value is set for the calculated dimming ratio for the dimming ratio calculating means, and the dimming ratio calculated for the hemoglobin switched by the switching means exceeds the range of the threshold. 13. The hemoglobin concentration measuring device according to claim 12, further comprising a display unit for displaying an alarm when the condition is detected. 14. A light source that emits at least three different light wavelengths of a near-infrared region as a first wavelength, a red region as a second wavelength, and a red-orange region as a third wavelength; A light receiving means for receiving the reflected light; and a light attenuation ratio for calculating a concentration ratio of carboxyhemoglobin and methemoglobin based on a change in a light receiving output signal at each wavelength from the light receiving means due to blood pulsation. Calculation means, for the dimming degree ratio calculating means, for the calculated dimming degree ratio, a predetermined threshold for carboxyhemoglobin and for methemoglobin is set, and at least one of carboxyhemoglobin and methemoglobin Display means for displaying an alarm when the calculated extinction ratio exceeds the threshold range. Hemoglobin concentration measuring device. 15. At least 790 to 1 as a first wavelength.
000 nm near infrared region, 640 to 67 as the second wavelength
5 nm red region, 590-660 nm as third wavelength
The hemoglobin concentration measuring device according to claim 1, wherein the region is a red-orange region. 16. The hemoglobin concentration measuring device according to claim 15, wherein the third wavelength is 621 nm. 17. A light source that emits a plurality of different light wavelengths, a light receiving unit that receives light emitted from the light source and transmitted or reflected through a living tissue, and a calibration value input that inputs at least one blood light absorbing substance concentration value Means for calculating a dimming ratio Φ between the respective wavelengths based on fluctuations of a light receiving output signal at each wavelength from the light receiving unit due to blood pulsation; and the dimming ratio Φ Having storage means for storing data relating to, using the data stored in the storage means and the blood light-absorbing substance concentration value input to the calibration value input means, at least retroactively oxyhemoglobin and methemoglobin A hemoglobin concentration measuring device, comprising a concentration calculating means for recalculating the concentration. 18. A light source that emits a plurality of different light wavelengths, a light receiving unit that receives light transmitted from or reflected by a living tissue emitted from the light source, an input unit for inputting a reference time point, and a blood pulsation. A light attenuation ratio calculating means for calculating a light attenuation ratio Φ between the respective wavelengths based on a variation of a light reception output signal at each wavelength from the light receiving means; and at least one of carboxyhemoglobin and methemoglobin A hemoglobin concentration measuring device comprising: a density value variation calculating means for calculating a density value variation from a reference time point on the basis of a density at a reference time point input by the input means for one density. 19. The hemoglobin concentration measuring device according to claim 18, wherein said input means is a calibration value input means for inputting a blood light absorbing substance concentration value, and said concentration value variation calculating means is said calibration value input means. By entering a temporary value as the blood light absorbing substance concentration value in
A hemoglobin concentration measuring device which calculates a concentration value variation after a reference time.